In textile machines such as spinning machines, roving frames and the like, especially ring spinning machines in the case of spinning machines, the drafting frame which is utilized for drawing the yarn, roving, slubbing or sliver, can include a lower belt against which the yarn is pressed by the upper belt of the pressing arm of the drafting frame.
This lower belt can pass around at least one roller which can be used to drive the lower belt and can have an upper pass guided by and supported by a guide rail about which the lower belt is deflected to form the return pass or stretch. This guide rail thus supports the upper stretch of the lower belt in the region in which it engages the strand to be drafted, and serves as the turning edge about which the upper stretch passes to form the return stretch. Hence, the guide rail can also be referred to as a deflection or return rail.
In many cases the lower belt, which passes around the drive roller and the guide rail, can be engaged by a tensioning stirrup which is spring loaded and serves to maintain a more or less constant tension on the lower belt. The tension on this lower belt can be adjustable by rotation of a rod in bores of which, shanks of the stirrups can engage.
DE 44 01 880 A1 describes a short roller belt for a drafting frame of this type which passes about a roller and a guide rail. The guide rail is composed of sheet metal and the return stretch is additionally guided as it passes off from the edge of this guide rail.
A belt table is formed in the drafting frame of DE 41 22 881 A1 which has a formation with surfaces extending to opposite sides of this formation. The formation is engaged formfittingly in a slide guide arrangement and a pivotal movement can be imparted to the table plate.
The plate and the formation can be comprised of a plastic.
It is also known to treat the surface of a guide rail of the type described so as to reduce the wear of the surface where it is engaged by the belt, e.g. by zinc plating, chromium plating or coating with an epoxy resin lacquer.